Reamer



Dec. 4, 1934.

III

I T. PEDIGO REAMER Filed Feb. 28, 1934 2 Sheets-Sheet l Dec. 4, 1934. T.PEDIGO 1,933,488

r REAMER Filed Feb. 28, 1934 2 Sheets-SheetQ Patented Dec. 4, 1934 FFICs era REAMER Luther T. Pedigo, Greensburg, Kans.

Application February 28, 1934, SerialNo. 713,363

5 7 Claims. (01. 255-76) This invention relates to well-drilling matralrib or stop lug 7, the sides of the body being chinery. open, as shownat 8, whereby circulation of "Inmany localities, the groundformationsare water or other fluid around the working parts is such thatit is impossible todrill wells to the facilitated and, consequently,lubrication of the 5 required depth without first running in thewellparts is effected. At its lower end, the body is casing to shut offcaving formations. Very often p d With a p d O We l CIOSS there areformations encountered which are hard Web or rib 9 which is disposedcentrally between and impervious and prevent the casing from the sidesof the body and serves as a guardto passing on down the holewhich hasbeen drilled resist and mi m e t cce s o foreign matte! 10 by a, bitthat i small enough to pass through to the intermeshing teeth on thecutters, and 6 the casing. When such formations are encounalso as a stopto limit e ward m vement Of tered, the h l b 1 the casing ,i enlargedthe cutters, all of which will be readily underby the use of what isknown as an under-reamer, stood upon re e e ce o the drawi and thepresent invention relates particularly Ah adjusting C eW y is mounted inthe to the construction of the under-reamer, the pp end Of the ody a dhas its shank ex- 70 object being to provide a reamer of novel contendedthrough the ope 5, s c a y wn, struction whereby a simple durable devicewill a 100k nut 11 being fitted -1 the pp 8 be provided comprising fewparts and eliminattremity 0f the Shank and Seating W n a eing a largeamount of machining which is neccess 12 Provided therefor in the uppernd f essary in manufacturing 'reamers heretofore the P joint 3, asShOWII- A 0011 Spring 13 ha 75 known. The invention is illustrated inthe ac- One end engaged in the y 14 Of this SCIeW y companying drawingsand will be hereinafter and itS Opposite end engaged in e pp e d fullydescribed, the novel features being particuof a V-Sheped bowed leafSpring S ea larly defined in the claims following the descrip- Springhaving its Side members d v g d wnn wardly and equipped at their lowerends with 0 In the drawings, eyes or hooks adapted to engage around pinsFigure 1 a View, partly in elevation and 16 inserted transverselythrough the upper ends partly in vertical section, of a reamer embodyingof the cuttel'e- The Cutters consist of a Su the present inventionstantially cylindrical main portion or body 17 Figure 2 is an edgeelevationof the Same. having an opening 18 therethrough to receive 8Figure 3 is an enlarged detail section showa joumel P 19, the ends ofWhich are received ing the Cutters swung inwardly into the posi 1nopenlngs 20 in the opposite side walls of the tion assumed when ther'eamer is being passed body, said openings being located at the cornersof the body at opposite sides of the central verdown or drawn up throughthe casing.

Figure 4 is a detail elevation of a portion tlcal plane of the body.Onthe1r opposed sides, 9 f the reamer head or body the cutter bodies 17are formed with gear teeth Figure 5 is ahorizontal section on the line21 Whlch mtermesh as Clearly Shown n Figof Figure 1. I ures land 3, sothat the movement of the cut- Figure 6 15a perspective View of one ofthe ters will besimultaneous and equal at all times,

Cutters removed and 1t may be noted that there is no strain upon theseinterrneshing gear teeth, all the In the drawings, the reference numeral1 instrain being carried by the journals 19 on meat-{es portmn of Casmgwhich has been their upper sides, the cutter bodies 17 are formed set-1F partly'dnued W811 The numem1 with, spaced lugs 22 which receive-the'ends of 5 2 Indicate? of my lmprmfed' the pins 16 so that the ends ofthe bowed spring reanfler 1s pmvlded at its upper end with 15 will beattached to the cutters and will cona P 301m 3 for attachment theregular stantly urge the cutters toward the expanded drilling stem. Thebody or head 2 1s constructed operating position shown in Figure Connectinternally with a chamber or recess 4, the side mg the lugs 22 is a Web23 which terminates 50 Walls of which diverge downwardly as clearlyshort of the outer surfaces of the respective win Figure 1, and from theupper Of lugs to form, when the webs of the two cutters Whic an Op 5eXtendS through the upper come together, cooperating recesses in thesides e rem ty 0f t d- Spaced below t reof the cutters which will fitaround the ribs or cess or chamber 4, on each side wall of the stop lugs7 on the body, as shown in Figure 5,

55 body, is a shoulder 6 from which depends a cenand thereby prevent thecutters swinging out- 1 1,0

wardly to an excessive degree. The cutting edges or blades 24 projectbeyond the sides of the respective bodies 17, as will be understood uponreference to Figures 2 and 5, and they are made convex so as to fitreadily within the casing or pipe 1, as will be understood. The bladesextend from the undersides of the respective bodies 1'7, as shownclearly in Figures 1 and 6, and at the junction of the blades and thebodies, in the outer sides thereof, are recesses 25 in which are mountedrollers 25 adapted to engage and roll upon the inner surface of the pipeor casing 1, when the reamer is being drawn upwardly or lowered throughthe pipe, as will be understood. As shown most clearly in Figure 5, theperipheries of the rollers are made convex so that "they will conform tothe concavity of the pipe and thereby facilitate the passage of thereamer therethrough.

The body 2 is provided, on its opposite sides, with vertically extendingribs 27 which will serve to reinforce the body and permit the Weight ofthe same to be minimized, and also will serve as guides to maintain thereamer properly centered within the pipe when being moved therethrough.

It will be understood from the foregoing description, taken inconnection with the accompanying drawings, that the spring arms 15constantly urge the lugs 22 and their connecting webs 23 toward eachother so that the cutting edges or blades will swing outwardly beyondthe sides of the body 2 to the position shown in Figure 1, to cutthrough the earth formation which has been encountered and through whichthe pipe cannot readily pass. The tension of the spring arms 15 will beregulated by adjusting the screw eye 10 so that the cutting edges willrock outwardly whenever they may clear the lower end of the pipe. Whenthe hole has been sufiiciently enlarged, the drill stem is drawnupwardly in the usual manner and the cutters will impinge against thelower end of the pipe, the rollers 26 engaging the pipe and yielding tothe impact so that the force of the spring arms will be overcome and thecutters will be rocked inwardly to the inoperative position shown inFigure 3. As before stated, the movement of the cutters will be equaland simultaneous, owing to the presence of the intermeshing teeth 21,and access of clay or other foreign matter to the teeth in suchquantities as to interfere with their successful operation will beprevented by the guarding extension 9. The device is exceedingly simpleand compact and as there are but few parts, it is not apt to get out oforder and will prove durable and efilcient in use at a times.- i

Having thus described the invention, I claim:

1. An under-reamer comprising a body, cutters journaled in the lower endof the body to rock outwardly to operative position or inwardly toinoperative position and provided with intermeshing gear teeth on theiropposed surfaces, interengaging elements on the cutters and the body tolimit the relative outward movement of the cutters, and a spring mountedin the body and connected with the cutters to constantly urge themoutwardly toward operative position.

2. An under-reamer comprising a body having a recessed portion in itslower end and provided with transverse shoulders on the inner walls ofsaid recessed portion, stop lugs depending from said shoulders, cuttersjournaled in the lower end of the body below the shoulders to rockoutwardly to operative position or inwardly to inoperative position andprovided with intermeshing gear teeth on their opposed surfaces, stopelements on the upper sides of the cutters adapted to impinge againstthe stop lugs on the body to limit outward movement of the cutters, andsprings mounted in the body and connected to the upper sides of thecutters to constantly urge them outwardly toward operative position.

3. An under-reamer comprising a chambered body provided with atransverse extension at its lower end, cutters journaled in the lowerend of the body at opposite sides of said extension to rock outwardly tooperative position or inwardly to inoperative position and provided withintermeshing teeth on their opposed surfaces in the vertical plane ofsaid extension, springs mounted in the chamber of the body and connectedwith the upper sides of the cutters to constantly urge them outwardlytoward operative position, and interengaging means on the cutters andthe body to limit their outward movement.

4. An under-reamer comprising a chambered body provided with transverseshoulders on the i T side walls of its chamber and depending stop lugsat the centers of said shoulders, cutters journaled in the body belowthe shoulders at opposite sides of the stop lugs to rock outwardly tooperative position or inwardly to inoperative position, lugs on theupper sides of the cutters adapted to impinge against said dependingstop lugs to limit the outward movement of the cutters, webs connectingthe lugs on the respective cutters and adapted to impinge against eachiroll upon the inner wall of a well casing, and

a bowed spring housed within the chamber of the body and having its endsconnected with the cutters to constantly urge the cutting edgesoutwardly to operative position.

LUTHER T. PEDIGO.

